Abstract: A technique for determining the position of a device involves generating a set of N measurements from signals transmitted by a respective set of N references devices, where the N measurements are suitable for determining a position of the device using N-lateration. Respective reliability metrics are generated for the N measurements based on information about uncertainty of individual measurements. An N-lateration computation is used to iteratively refine an estimate of the position of the device. Each iteration includes adjusting the estimate of the position of the device based on a least squares function that minimizes a sum of squares of errors between the N measurements and distances between the estimate of the position of the device and the N reference sources. The least squares function is weighted in accordance with the reliability metrics for the N measurements.

Abstract: A rolled material holder includes rotatable disks as base members with pivotable arms for holding opposing open ends of a cylinder having a roll of material. The rotatable disks allow an installer to mount the holder on any surface without limitation to being just horizontal or just vertical. Each of a pair of side frame members has a cavity, and the disks are positioned in the cavities and have a selectable orientation within the respective cavity of the side frame members. Each base member has a recess in which are mounted a pair of arms for holding the cylinder at the opposing open ends.

Abstract: A lidded container for growing, transporting and storing nursery plants. The container assembly comprises in combination an open-topped container dimensioned to receive the root structure of a plant and a lid which fits within the open top of the container. The lid has a central opening dimensioned to receive the stem or trunk of a plant and a radial slot of predetermined width communicating the opening with the exterior. A slide block or other closure is mountable in the slot. It slidably engages the slot margins when the lid is in its operative position, closing the open top of the container. Frictional interengaging means, such as a plurality of parallel, closely-spaced ribs on the upper inner margin of the container, releasably maintains the top in the closed condition of the container.